True bypass with battery switch?

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ollelolle
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Post by ollelolle »

Hi!

I am currently modifying some, and building some new pedals. One of these is a Zvex Fuzz Factory which I am going to build into my guitar.
My question then is, is it possible to somehow wire a true bypass which also switches off the power supply to the pcb?
Seeing as the guitar will be plugged into a jack most of the time during shows, I think it would be best to be able to switch the Fuzz Factory off when it's not being used.

Best regards,
-ollelolle

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FiveseveN
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Post by FiveseveN »

Short story: it's not. Don't bother.
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deltafred
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Post by deltafred »

It's possible but it is probably going to give you a thump or pop when you energise the circuit unless you build in a delay before activating the bypass. I am guessing this is beyond your capabilities if you need to ask.

Years ago I went through the phase of wanting to build effects into my guitar but then realised that there are very few minuses to pedals and way more pluses.
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Nocentelli
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Post by Nocentelli »

ollelolle wrote:Seeing as the guitar will be plugged into a jack most of the time during shows, I think it would be best to be able to switch the Fuzz Factory off when it's not being used.

Best regards,
-ollelolle
If you are determined to build it into the guitar, you'll have to make do with a TRS output jack on the guitar, and the usual "unplugging the jack cuts the power" like on a standard battery-powered stompbox input. The fuzz factory circuit supposedly draws little in the way of current so will last for many hours, no worse than what an active bassist puts up with (and original fuzz factories had no DC jack sockets either, so you had to remember to unplug them). Virtually no pedal designs i know of cut the power in bypass; The only one I have come across is the Danelectro Cool cat vibe, and that is probably because it uses a filament lamps so the current draw is huge, and it is pretty useless unless you modify it to correct this "defect" since the effect takes several seconds to kick in after pressing the footswitch. At the very least, your caps would have to charge, and you may well also get a power-on thump through the speakers as mentioned.
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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induction
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Post by induction »

I agree that it would be a bad idea to disconnect power with the bypass switch.

However, it is possible to simply add an additional spst switch to disconnect power, so you don't have to unplug the guitar to power it down. Whether that's a good idea or not depends on how you intend to use it. There will be an intrinsic hazard of forgetting to power up the circuit before engaging it, of course. Call me a pessimist, but I believe that the likelihood of this happening is directly proportional to the number of people watching at the time. If you gig with it, it's nearly certain that sooner or later you will engage the circuit for a solo and lose signal entirely because you forgot to power it up first.

If you do decide to do it, I'd still use a TRS plug as a secondary on/off switch, as Nocentelli recommended, since it is also nearly certain that sooner or later you'll forget to turn it off.

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deltafred
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Post by deltafred »

induction wrote:Call me a pessimist, but I believe that the likelihood of this happening is directly proportional to the number of people watching at the time. If you gig with it, it's nearly certain that sooner or later you will engage the circuit for a solo and lose signal entirely because you forgot to power it up first.
^ This.

Last night our singer/guitarist forgot to switch his IEMs on when we started the second set. Cue a gap in the guitar while he switched them on.

I forget to switch mine on about 40% of the time, but I only sing lead on a couple of songs so it is not so important and I can usually hear enough from the FOH to get by singing backing vocals until the end of the first song.
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ollelolle
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Post by ollelolle »

Thank you for all replies.
This concludes my suspicion (which I know I didn't write). I will go for a standard true bypass switch, and do the output jack as a power switch.
I'll keep you updated with the process! :D

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